I loveeeeeee their smoothie option - you get a cup, and fill it up with any yogurt or fruit that you want, and they'll blend it together with some juice for you. I'm a huge smoothie snob and it's hard to get stuff that tastes good, so being able to make my own is so fun!
They have a lot of cool flavors to try, but a lot of them are on rotation so make sure to get them before they go away!